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Dec. 17th Tropaeolum

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Diagram (1) (Copied by Frank)

Fig. 13.

Dots all of same size, except the first one which is always to be rather larger than the others.

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Circumnutation of arched plumule, traced on horizontal glass, magnified about 27 times — seedling dimly illuminated from above

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Chapter 0 9

(Fritz Müller also states that an endemic a species of Bignonia & Tabernœmontana echinate are both sterile with their own pollen in their native country of Brazil *(*Botany Zeitung 1868 p 626, and 1870 p 274)

Several amaryllidaceous & Liliaceous plants are in the same predicament. Hilder brand observed with care Corydalis cava and found it completely self-sterile.*(*Report of the International Hort. Congress 1866); but according to Caspary a few self-fertilised seeds are sometimes produced & Corydalis C. halleri is only slightly self-sterile, and C. intermedia not at all so. *(*Botany Zeitung June 27 1873). In another Fumariaceous genus Hypercoum, Hildebrand observed *(*Jahrb. für Wiss. Botanik Bd VII p 464) that H grandiflorum was highly self-sterile, whilst H procumbens was fairly self-sterile. Thunbergia alata kept by me in a warm greenhouse was self-fertile sterile early in the season, but at a later period produced spontaneously many self-fertilised fruit. So it was with Papaver vagum. Another species, Papaver alpinum was

[Cross and self fertilisation, p. 331: "Fritz Müller also states that a species of Bignonia and Tabernaemontana echinata are both sterile with their own pollen in their native country of Brazil.† Several Amaryllidaceous and Liliaceous plants are in the same predicament. Hildebrand observed with care Corydalis cava, and found it completely self-sterile;‡ but according to Caspary a few self-fertilised seeds are occasionally produced: Corydalis halleri is only slightly self-sterile, and C. intermedia not at all so.§ In another Fumariaceous genus, Hypecoum, Hildebrand observed that H. grandiflorum was highly self-sterile, whilst H. procumbens was fairly self-fertile. ('Jahrb. für wiss. Botanik' B. 7 page 464.) Thunbergia alata kept by me in a warm greenhouse was self-sterile early in the season, but at a later period produced many spontaneously self-fertilised fruits. So it was with Papaver vagum: another species, P. alpinum, was found by Professor H. Hoffmann to be quite self-sterile excepting on one occasion;¶ whilst P. somniferum has been with me always completely self-sterile.
† Ibid 1868 page 626 and 1870 page 274.
‡ 'Report of the International Horticultural Congress' 1866.
§ 'Botanische Zeitung' June 27, 1873.
¶ 'Zur Speciesfrage' 1875 page 47."]